Binary code relay



Oct. 9, 1962 A REYNOLDS, JR 3,058,095

BINARY CODE RELAY Filed Aug. 22, 1958 2 Sheets-Sheet 2 5/64 14 Ml/WZSZSm E [I] Z [I] Z] [I] [I Q [I] 1:

[OI/16754620550 R A H E [OI/1075426205450 H fi' mm'cm/msza IN VENTOR.MAW/Pf)! 6194/6 if M0105 J? J 197' 7 GPA/f V- 9 Claims. (Cl. 340-164)This invention relates to remotely controlled relays and moreparticularly to a switch actuating relay responsive to a binary codesignal.

Relays of this general type are primarily intended for use in a systemwhich includes a master signal transmitter and a plurality of relaysconnected to a common power supply line. Each of the relays is adjustedto respond to a particular coded signal pattern and thus the transmittercan selectively actuate any desired relay by sending the proper code onthe power line. Systems of this nature have found particular utilitywhen installed on a regular 60 cycle, A.-C. power line with the relaysbeing responsive to high frequency signals superimposed on the line bythe transmitter. In this way, appliances receiving power from the linecan be remotely controlled from a central station. Reference is made tomy Patent No. 2,852,704 and Patent No. 2,852,- 705, both issuedSeptember 16, 1958, and assigned to the same assignee of the presentapplication, which illustrate such a system.

One of the difficulties in setting up a system of the type referred toabove is the problem of providing a simple and completely reliable codedsignal relay that is immune to spurious transient signals which arefound to occur at random in an A.-C. power system. Such transientsignals have abrupt wave fronts comprising many frequency components andare commonly generated by various forms of heavy duty electricalequipment which may be installed in the system. Often a spurious signalincludes a component having the frequency at which the relays are set torespond and thus a false code is transmitted on the power line which hasproved troublesome in remote control systems of this type.

It has been proposed to deal with this problem of transient signals byconstructing relays which respond only to signal impulses that aresustained for a predetermined time interval. In a practical case, theinterval may be approximately two seconds, that is, each signal impulseof the code signal must be of a predetermined duration, for example twoseconds, in order to actuate the relay. In this Way, transient signals,which are of only quite short duration, cannot cause false relayactuation.

This solution however, has presented a further problem. When using asignal made up of signal impulses having an appreciable time length, thenumber of different signals in the code has heretofore been rather smallsince, for practical considerations, the time inter val within which acomplete signal is to be sent must be reasonably limited. Againreferring to a practical case, it is desirable to complete a signalwithin a one minute interval. This factor has limited the number ofrelays on a single circuit which can be selectively actuated by a codedsignal.

Accordingly, it is the primary aim of the present invention to provide anovel coded signal responsive relay, immune to spurious, transientsignals, which will respond to a single selected code signal of a verylarge group of possible signals. In this way, a large number of relaysembodying the invention can be selectively operated on the same circuit.

It is also an object of the invention to provide a relay of the abovetype which is simple in design and completely reliable in operation.

3,58,095 Patented Oct. 9, 15362 With more particularity, it is an objectto provide a relay of the type characterized above which is c nstructedof conventional cam-controlled switches operated by an ordinary timingmotor so as to be economical to manufacture. It is a related object toprovide such a relay having few parts, and those operating under verylight mechanical forces, so that the relay remains reliable and accurateover a long and trouble-free service life.

In one of its more detailed aspects it is an object of the invention toprovide a novel relay of the type dis cussed above which can supply acontrolling current impulse to either of two devices in response to afurther code signal transmitted remotely from the central controlstation.

Other objects and advantages of the invention will become apparent uponreading the following detailed description and upon reference to thedrawings in which:

FIGURE 1 is a schematic wiring diagram of a coded signal relayconstructed in accordance with the present invention;

FIG. 2 is a fragmentary schematic diagram showing a typical system inwhich the relay appearing in FIG. 1 may be utilized;

FIG. 3 is a chart detailing the sequence of contact set operation in therelay shown in FIG. 1; and

FIG. 4 is a fragmentary perspective view of a time delay device utilizedin the FIG. 1 relay.

While the invention will be described in connection with a preferredembodiment, it will be understood that I do not intend to limit theinvention to that embodiment. On the contrary, I intend to cover allalterations, modifications and equivalents as may be included within thespirit and scope of the invention as defined by the appended claims.

Turning now to FIG. 1, there is shown a relay 10 embodying the presentinvention and provided with terminals 11 adapting the relay forconnection to an A.-C. power system. The A.-C. system may include aplurality of similar relays 10a in addition to a high frequencytransmitter of any conventional type which is efiective to superimpose ahigh frequency signal on the normal 60 cycle A.-C. power system (seeFIG. 2). In the illustrated embodiment, the relay 10 is provided withoutput terminals 12 and 13 which are connected to devices 14 and 15,respectively, that are cont-rolled by the relay 10 in accordance withthe reception of signals on the power system. It will be understood thatthe relays 10a may control additional devices and that, if desired, therelays 10 and 10a may be employed to control but a single device 14 or15.

In order that the relay 10 may detect high frequency signals transmittedon the A.-C. power system, the relay includes a high frequency signalreceiver 24) coupled across the terminals 11. The receiver 2% may be ofany convenient type such as are well known in systems of this nature.

In accordance with the present invention, the relay 10 includes bothmeans responsive to signal impulses in a serial binary code pattern andmeans for cycling through a serial binary code pattern, the arrangementof these means being such that if the received impulses coincide withthe predetermined pattern, the output terminals 12 and 13 are energizedto operate one of the devices 1 15. Preferably, the binary, ortwo-condition, code is simply a yes-no or on-off code in which thereeither is or is not an electrical impulse during each interval of a setnumber of successive timed intervals. In the present case, a binary codeis selected in which there are five twosecond periods spaced two secondsapart during which there may or may not be an electrical impulse, andthese spaced twosecond periods comprise the binary code portion of acomplete relay actuating signal which has a total time duration 3 of 60seconds. The nature of the complete signal including its binary codeportion will become evident as this discussion proceeds.

In the illustrated embodiment, the means responsive to the coded signalimpulses on the A.-C. power system include sets of contacts 31, 32controlled by a relay 35 which is coupled to the receiver 20. Thecontacts 31 are normally open and the contacts 32 normally closed. Whena high frequency signal impulse is impressed on the A.-C. power system,the receiver 20 is eifective to energize the relay 35 so as to close thecontacts 31 and open the contacts 32. These contacts thus close and openrespectively in accordance with the serial signal pattern transmitted onthe power system.

In the preferred device, the means in the relay for cycling through apredetermined serial binary code pattern comprises sets of contacts 41,42 which are controlled by cams 43, 44, respectively. The cams 43, 44are secured to a cam shaft 45 that is driven by a timing motor 46. Bothof the contact sets 41, 42. are normally closed but they are opened bylobes on the cams 43, 44 as the cams are rotated by the timing motor 46.It will therefore be appreciated that by providing a series of annularlyspaced lobes on the cams 43, 44, the contacts 41, 42 can be made to openand close in a predetermined pattern.

In order to energize the output terminals 12, 13 only if there iscoincidence between the relays predetermined code pattern and thereceived signal impulse code, the contacts 31, 32 and 41, 42 are coupledto a two-condition relay 54 so that the condition of the relay 50changes unless there is the desired coincidence. In the illustratedembodiment, the relay 50 is energized, or picked up, before the binarycode is transmitted on the A.-C. power system, and the contacts 41, 42shunt the contacts 31, 32 so that when the contacts 31 close and thecontacts 32 open, the contacts 41 will open and the contacts 42 willclose to maintain a circuit through the relay 5t} and hold it in.

For initiating the operation of the timing motor 46 and for conditioningthe relay 50 prior to transmission of the binary signal, the relayincludes a set of normally closed initiating contacts 51 controlled by acam 52 carried on the shaft 45. Also, a complete relay actuating signaltransmitted on the power system includes an initiating signal impulse.When the first high frequency signal impulse, the initiating signal, isreceived by the relay 10, the receiver is effective to energize therelay 35. This closes the contacts 31 and completes a circuit throughthe contacts 31, the relay 50, the closed contacts 51, and the closedcontacts 42, that is eifective to energize the relay 54. When relay 50picks up, it closes two sets of contacts 53, 54. Closing of the contacts54 completes a circuit energizing the timing motor 46. As the timingmotor begins to rotate the cam shaft 45, a motor seal-in cam 55 securedto the shaft 45 is rotated so as to close the normally open contacts 56which by-pass the contacts 54 and seal-in the motor 46.

As the cam shaft 45 begins cycling, the lobe 43a on cam 43 releases andallows the contacts 41 to close so that a circuit is completed throughthe contacts 41, the relay 50, the then closed contacts 53 and thecontact sets 32, 42. Further rotation of the cam shaft causes the cam 52to open the contacts 51 so as to shift control of the relay 50 to thecontact pairs 31, 32 and 41, 42 and, because of the circuit justdescribed through contacts 41, 53, 32 and 42, the relay 50 remainsenergized.

Following the initiating impulse, the binary code portion of thecomplete relay actuating signal is transmitted as a set of five camlobes on the earns 43, 44 operate the contacts 41, 42 in a predeterminedcode pattern. In the preferred embodiment, both sets of contacts 41, 42are closed at the start of the serial binary signal. Then, in the fivesuccessive two-second timed periods, the contacts are alternately openedfor brief periods in a predetermined order determined by the cams 43,44. In the illustrated example, the lobe 43b opens the contacts 41during the first of the five periods, then lobe 44a opens the contacts42 during the second period, lobes 43c and 43d open the contacts 41during the third and fourth periods, and finally lobe 44b opens thecontacts 42 during the final fifth period.

If, during the opening and closing of the contacts 41, 42 by the earns43, 44, a pattern of signal impulses is received on the A.-C. powersystem so that each time the contacts 41 are open, the contacts 31 areclosed, and each time the contacts 42 are opened, the contacts 32 areclosed, then the relay 5th will remain energized. It can therefore beseen that the relay 50 will remain energized only if there iscoincidence between the predetermined order in which the contacts 41, 42are operated and the pattern of a set of five high frequency impulsestransmitted on the A.-C. power system.

Since the illustrated relay 10 responds to a binary code of five digits,there is provided a total of thirty-two possible binary codecombinations which can be selected by the proper formation of the cams43, 44. To further multiply the number of possible codes, and thus thenumber of such relays which can be selectively operated on one A.-C.power system, the complete relay actuating signal includes a timedsignal portion as well as the binary signal portion.

The timed signal portion is also divided into five successive two-secondintervals spaced two seconds apart. During one of these five timed codeperiods, a lobe 436 on the cam 43 again opens the contacts 41 and,unless a high frequency signal impulse is being simultaneously receivedby the relay 10, the relay 50 will be dropped out. The five timed codepossibilities are effective to multiply the thirty-two binary codecombinations by five, so that the total number of possible codecombinations for which the relay 10 may be set equals 160. That is, byproperly forming the cams 43, 44, 160 different relays can beselectively operated on a single AC. power system.

To energize the output terminals 12, 13 when the proper coded signal hasbeen received and the relay 50 remains energized, an output signal cam60 is provided controlling a set of normally open contacts 61. At the'end of one complete revolution-of the cam shaft 45, the

cam 60 is ellective to close the contacts 61 so as to complete a circuitfrom the relay 50 to the output terminals 12, 13. If current is flowingthrough the relay 50, that is, if the relay 50 is still picked up,closing of the contla2cti361 will transmit a signal impulse to theterminals So that the single relay 10 may control either one of the twodevices 14, 15, the output terminals 12, 13 are selectively energized bythe contact 61 through a switch 65 controlled by the relay 35. Normally,the switch 65 completes a circuit from the contact 61 to the outputterminal 12, but when the relay 35 is picked up, the switch 65 completesa circuit from the contact 61 to the terminal 13. In this way, if afinal signal impulse is transmitted on the A.-C. power system at thetime during which the contacts 61 are closed by the cam 60, then anoperating signal is transmitted through the switch 65 to the terminal 13and the device 15. If, however, no final signal impulse is transmittedthen the operating signal caused by closing of the contacts 61 isdirected by the switch 62 to the terminal 12- and the device 14. Thus, asingle additional signal impulse permits the relay 10 to selectivelycontrol either one of the two devices 14, 15.

For. the purpose of preventing operation of the relay 10 by spurious,transient signals, a time delay device is provided for coupling thetiming motor 46 to the cam shaft 45. In the present embodiment, the timedelay device 70 comprises a spring biased, lost motion drivingconnection between the output shaft 71 and the cam shaft 45. Thearrangement is such that when the motor starts rotating, it mustovercome the spring force and pick up the lost motion before the camshaft 45 begins rotation. To provide the lost motion connection, theoutput shaft 71 of the motor carries a disc 72 which is mountedconcentrically with, but independently of, the cam shaft 45. The disc 72rotates the cam shaft 45 by means of a pin 73 extending axially of thecam shaft through a hole 74 of somewhat greater diameter formed in thecam 55. It can be seen that when the pin is disposed at one edge of thehole 74, the motor 46 must rotate the disc 72 through a distanceapproximately equal to the diameter of the hole until the pin 73 engagesthe opposite side of the hole and imparts a rotational force to the cam55.

To insure that the disc 72 and the motor 46 are properly backed off sothat the pin 73 is adjacent the proper edge of the hole '74, a torsionspring 75 is fixed to the cam shaft 45 and is tensioned to exert aresilient force against the pin 73 in a direction opposite to thatimparted by the motor 46. It can thus be seen that momentaryenergization of the motor 46, caused by the brief closing of thecontacts 31 and momentary energization of the relay 50 as a result ofspurious transient signals being picked up by the high frequency signalreceiver 26, will only cause the disc 72 to begin revolving so .as tocarry the pin '73 across the hole 74. Upon the almost immediatede-energization of the motor 46 following the transient signal, thetorsion spring 75 will return the pin 73, disc 72 and the motorarmature, back to their original starting positions. It will be apparentthen that the operation of the relay 1!) can be initiated only byenergizing the motor 46 for a sustained predetermined period, which willbe the case when a true signal impulse of several seconds duration istransmitted on the A.-C. power system. In a practical system, initiatingimpulses of from three to four seconds duration have been found to beeffective.

To hold the cam shaft 45 and the cam 55 in their starting positionsagainst the reactive force exerted by the torsion spring 75, theinherent detenting eifect provided by the switch actuator for thecontacts 56 is utilized. As can be seen in FIG. 4, the contacts 56 areprovided with a resilient switch actuator 80 having a detent portion 81whichdrops into a notch-like drop-off portion 82 formed in the cam 55.It will be understood that the engagement of the switch actuator 80within the drop-01f portion 82 will hold the cam 55 and the cam shaft 45in their respective starting positions with a detent-like action. Whenthe motor 46 remains energized for a time sufficient to bring the pin 73into engagement with the opposite side of the hole 74, the cam 55 willbe rotated so as to bring the detent portion 81 of the switch actuatorout of the cam drop-off portion 82 so that the contacts 56 are closedand the operating cycle of the motor 46 initiated.

In order to minimize the resilient force required to be exerted by thetorsion spring 75, while insuring that the force is suflicient toback-off the disc 72 and the motor 46, the motor preferably includes anautomatically operating clutch of the type which is commonly employedfor such purpose In clutch motors of this type, the motor armature isautomatically engaged with the power output driving train uponenergization of the motor winding, and is disengaged upon thede-energization of the motor winding. An example of a motor of this typehaving such an automatic clutch construction may be seen by reference toUS. Patent No. 2,234,040, to Schennels, issued November 9, 1943. It willbe suificient for present purposes to observe that the armature in themotor 46 is coupled to the output shaft 71 only when the motor isenergized. When the motor is only briefly energized through the actionof a spurious signal causing the contacts 31 to flutter momentarily, theoutput shaft 71 and the disc 72 are briefly advanced by the motorarmature and then are completely disconnected from the armature.

rotate only the disc 72 initial starting positions, the entire armatureof the Rsum of Operation Having observed the structure of the relay 10,a complete understanding of the invention can be best obtained bybriefly considering an operating cycle during which the relay isactuated for operating one of the devices 14, 15. Having particularreference to FIG. 3, the complete relay actuating signal includes firstan initiating or start impulse which has approximately a four secondduration. This impulse energizes the relay 35 so as to close thecontacts 31 and complete a circuit through the relay 59, the contacts51, and the contacts 42, which is effective to energize the relay St).The relay immediately picks up and the contacts 54 are closed energizingthe motor 46. Since the contacts 54 remain closed for the duration ofthe long start signal impulse, the lost motion in the device 7d is takenup and the cam shaft 45 begins rotation. This causes the cam 55 to closethe contacts 56 and thus complete a circuit sealing-in the motor 46 forone complete revolution of the cam shaft 45.

As the cam shaft 45 rotates, the contacts 41 close and the contacts 51are opened so as to turn control of the picked-up relay 51 over to thecams 43, 44. The relay 5%) remains energized through a circuit includingthe contacts 53, either set of contacts 31, 41, and either set ofcontacts 32, 42.

Ten seconds following the start of the initiating signal, the binarycode portion of the signal is transmitted on the power system. The camlobes 43b, 43c, 43d, 44a and 44b successively open the contacts 41, 42.Each time the contacts 41 are opened, a signal impulse is receivedclosing the contacts 31, and each time the contacts 42 are opened, nosignal impulse is received so as to maintain the contacts 32 closed. Inthis way, the relay 5%} remains energized through the binary codeportion of the relay actuating signal.

At thirty seconds past the initiation of a coded signal, the timed codeportion of the signal begins. Through this period the relay Stl remainsenergized since both the sets of contacts 32, 42 are closed and thecontacts 41 are also closed. However, during one of the five successiveintervals during the timed code portion of the signal, the cam lobe 43eon the cam 43 is effective to open the con- 41 are open and thusmaintains the relay 5! in its ener- At fifty seconds past the start ofthe actuating signal, the cam 60 closes the contacts 61 so that theterminals 12, 13 are energized from the circuit passing through therelay 50. If no final signal is received to energize the relay 35, thecontacts 61 complete a circuit through the switch 65 and the terminal 12to the device 14. If a final on-off signal is received, then the relay35 will pick up and the switch 65 will complete a circuit from thecontacts 61 through the terminal 13 to the device 15.

Following the complete relay cycle, that is 60 seconds after the startof the complete relay actuating signal, the cam shaft 45 completes onerevolution and the contacts 41 open to drop out the relay 50. This opensthe contacts 54 and, simultaneously, the cam 55 opens the contacts 56 sothat the timing motor 46 is de-energized and the relay again assumes itsstandby condition.

It will be understood that the code signal to which the relay 16 isresponsive can be easily changed by substituting cams of a slightlydifferent configmration for the cams 43, 44. It will also be observedthat the relay It can be quite economically constructed since itutilizes only easily formed, conventional cam-controlled switches, and atiming motor and relays of standard design.

I claim as my invention:

1. In a code responsive relay for connection to a line on which istransmitted a binary code made up of a pattern of successive signalimpulses, the combination com prising, a first relay having firstcontacts normally open and second contacts normally closed, means forenergizing said relay responsive to on and off signal impulses foralternating the condition of said first and second contacts inaccordance with the pattern of said impulses, a timing motor,two-condition cam switch means cyclically controlled by said motor sothat the condition of said cam switch means is varied in a predeterminedcode pattern during said cycle, means including a second relayelectrically connected to said first relay contacts and said cam switchmeans so as to particularly respond to signal impulses received in apattern exactly corresponding to said predetermined code pattern, outputterminals alternately connectable to said line through said last namedmeans and said first relay, and means including said cam switch meansresponsive to exact correspondence between said pattern during saidcycle for energizing said one of said output terminals so as to operatea device connected thereto.

2. In a code responsive relay for connection to a line on which istransmitted a code made up of a pattern of successive on and oil signalimpulses, the combination comprising, a two-condition relay having firstcontacts normally open and second contacts normally closed, meansresponsive to said on and ofi signal impulses to energize said relay foralternately opening said second contacts and closing said first contactsin accordance With the pattern of said impulses, a timing motor, a pairof cam controlled contacts cyclically operated by said motor uponreceipt of a starting impulse, one of said cam controlled contacts beingopen and the other closed in a predetermined code pattern during saidcycle, code responsive means including said two-condition relayelectrically connected both to said first pair of contacts and said camcontrolled contacts so that the condition of said code responsive meanschanges unless signal impulses are received in a pattern exactlycorresponding to said predetermined code pattern, output terminalsalternately connectable to said line, and means responsive to said coderesponsive means maintaining an unchanged condition during said cyclefor energizing one of said output terminals so as tooperate a deviceconnected thereto.

3. In a code responsive relay for connection to a line on which istransmitted a code made up of an initiating signal impulse and a patternof successive on and off signal impulses, the combination comprising, afirst pair of contacts, means responsive to said on and off signalimpulses for opening one and closing the other of said first pair ofcontacts in accordance with the pattern of said impulses, a cyclicallyoperable timing motor, a pair of cam controlled contacts intermittentlyoperated by said motor during its cycle so that one of said camcontrolled contacts is opened and the other closed in a predeterminedcode pattern during the cycle, means for cycling said motor when saidinitiating signal impulse is received, means including a two-conditionrelay electrically connected both to said first pair of contacts andsaid cam controlled contacts so that the relay is picked up and held inonly if signal impulses are received in a pattern exactly correspondingto said predetermined code pattern, output terminals, and meansresponsive to said relay maintaining its picked up condition at the endof said cycle for energizing one of said output terminals so as tooperate a device connected thereto.

4. In a code responsive relay for connection to a line on which istransmitted a code made up of a pattern of successive on and off signalimpulses, the combination comprising, a first pair of contacts, meansresponsive to said on" and off signal impulses for opening one andclosing the other of said first pair of contacts in accordance with thepattern of said impulses, a timing motor energizable by receipt of astarting impulse and continuously operable through a predetermined timecycle, a pair of cam controlled contacts cyclically operated by saidmotor, one of said cam controlled contacts being open and the otherclosed in a predetermined code pattern during said cycle, meansincluding a two-condition relay electrically connected both to saidfirst pair of contacts and said cam controlled contacts with each camcontrolled contact shunting a respective one of the first pair ofcontacts so that the condition of the relay changes unless signalimpulses are received in a pattern exactly corresponding to saidpredetermined code pattern, output terminals, and means responsive tosaid relay maintaining an unchanged condition during said cycle forenergizing one of said output terminals so as to operate a deviceconnected thereto.

5, A binary coded relay responsive to a predetermined time sequentialbinary pulse code consisting of on and off signals, comprising incombination, first and second line terminals for connection to a sourceof energization, a holding relay connectable in circuit to each of saidline terminals and means operable by said relay when connected andenergized establishing an output circuit, a signal responsive relayincluding switch means connected so as to connect said holding relay tosaid first line terminal when an on signal is received and operable toconnect said holding relay to said second line terminal when an ofisignal is received, time controlled switching means operable to connectsaid holding relay to said first line terminal when a properly sequencedoii signal is received and operable to connect said holding relay tosaid second line terminal when a properly sequenced on signal isreceived in a predetermined code whereby upon receipt of saidpredetermined code, said holding relay maintains establishment of saidoutput circuit.

6. The combination defined in claim 5 further defined in that saidholding relay when de-energized disconnects itself from said signalresponsive relay and said switch means and when energized connectsitself in circuit with said signal responsive relay and said switchmeans.

I 7. The combination defined in claim 6 and time controlled switchingmeans for temporarily connecting said 0 holding relay in circuit withsaid signal responsive relay and said switch means upon initial receiptof a code.

8. The combination of claim 5 and second switching means adapted to,connect said output circuit to an output terminal at the termination ofreceipt of said predetermined code. 7 l

9. The combination of claim 7 and second switching means adapted toconnect said output circuit to an output terminal at the termination ofreceipt of said predetermined code.

References Qited in the file of this patent UNITED STATES PATENTS1,205,460 Lyons Nov. 21, 1916 1,924,795 Lipmann et al Aug. 29, 19332,229,697 Koenig Jan. 211, 1941 2,712,898 Knutsen July 12, 19552,801,405 Oliwa July 30, 1957 2,821,696 Shiowitz et al. V Jan. 28, 1958FOREIGN PATENTS 271,755 Switzerland Feb. 16, 1951

